Valve



June 27, 1939. w N V N 2,163,800

VALVE Original Filed Sept. 8, 36 2 Sheets-Sheet 1 i 1 1 I I i an 3; a 1

\/ Z Zhwentor H. W. NEVIN June 27, 1939.

VALVE Original Flled Sept. 8, 1936 2 Sheets-Sheet 2 luncutor NM MW x w Im 5 m .wh

' Patented June 27,

UNITED STATES.

PATENT ome 'porationotDelavru-e Original application September a, ma.semi no.

- 99,775. Divided and this application February 12.1937, Serial No.1st,? 7

11 Claims. (cl. 137-458) This invention relates to means for automati-H1 caliy opening and closing the lbwpressure or suction line of arefrigeration system by empl ing the diilferential in pressure betweenthe 5 pressure or liquid line of the system and the 1 pressure line. r

'I'hisfapplicatibn is a division oi'my application entitledRefrigeration system, Serial No. 99,775, filed Septemberfii 1936.

One of the objects of the invention is to pro-u v ld e means forautomatically opening and closing the suction line from the evaporatorin a prompt and positive manner so as to accurately control thetemperature of the refrigerated space. v

Another object of the present invention is to provide for refrigerationsystems a simple, practical and efllcient automatically operatingpressure actuatedsuction stop valve of strong, durable as andcomparatively inexpensive construction de-' signed to be connected inthe suction line and the liquid line of a refrigeration system betweenthe float valve of the cooling coil and theliquid stop valve of therefrigeration system and adapted as to prevent further retrigerativeefl'ect at a predetermined time as for instance when a thermostat in therefrigeration chamber operates to close the liquid stop valve.

A further object of-the invention is to provide "ill a pressure actuatedsuction stop valve of this character adapted to prevent the flow of gasthrough the suction line to the condenser or v compressor when theiiowof liquid through the q idlineisshutoifand ajfreeflowof s liquid throughthe liquid line and a free flow of gas through the suction line when theliquid stop valve is open'and capable also of eflectively pre-f ventingcounterflow of gas through it ,when the liquid flow is b Avfurtherobject of the invention is to provide a pressure actuated suction stopvalve adapted to allow considerable liquid pressure to'be applied to 1whereby a positive opening of the suction line is eiiected when theliquid stop valve is "5 openedtopermitflowoftheliquidtothecoqlilil orexpansion coil.- V A further object of the invention isto'vprovide'means for controlling the speed of operation or-'thesuctionstopvalvesothattheopeningofthe same may be retarded to thedesired extent and isfull opening of the suction stop valve at the'desired time with relation to theliquidtothecoolingculll,

Another object or the invention is sesame f a pressure actuated suctionstop valve which liquid. In the evaporator, the ammonia passeswillbecharacterised by aniy-lowcost of operation and maintenancecompared with v the means heretofore employed for controlling the flowthrough: the suction and liquid lines of arei'rigerationsystem. f5

Aswillbe apparent fromthedescriptionwhich follows, the present inventioninvolves the introduction of a stop valve interposed athwart the highpressure section and the low pressure section of a fluid line havingrelatively high pressure and low pressure eectlons.

It is well known of course, that refrigeration systems employ a fluidline having relatively high pressure and low pressure sections Theammonia comes from the compressor under relatively'high pressure andproceeds through the high pressure section of the line to theevaporator, existing in this sectionofthe line as a to the gaseous phaseandreturns to the compressor under relatively lower pressure to becompressed and recirculated. g

It is, of course, common to provide 'thermostatic means for stopping theflow of liquid from the compressor, this normally being eflectedby theuse of a thermostat which operates to stop the operation of thecompressor at a predetermined tempratute of the reirigersted'spsce.

Refrigeration plants may be considered for present purposes as being oftwo types, namely,

such installations, a separate thermcstatin each continuestooperate.This tlon is to operate amssnetie liquidintheliquidlineleadingtothechsmherin-tion.'siterthenowetliquidtotheevspontor 10 Magnetic stop valves havebeen unsatisfactory in practice because of frequent failure due to thenecessity of employing an unloader or pilot valve. The differential inpressure in the line is obviously too great to permit positive operationof a valve solely by the employment of a solenoid of any practicabledimensions. The usual solenoid employed has a total lifting power of butthree to five pounds and must operate against a pressure differential ofaboutthirty pounds per square inch, or a total pressure of,

about ninety-four pounds in a two inch line. An

unloader employs the pressure of the line to unseat the valve when thesolenoid opens a needle valve to reduce the pressure within the unloaderpiston.

The necessity of closely fitting the piston in the valve cylinder toprevent excessive gas leakage often results in the piston sticking andthe coil burning out. tion on the refrigerated space unless the suctionline is opened, it is obvious that the failure of the valve istantamount to a failure of the system. It is'immaterial whether thefailure of the valve is due to sticking or the burning out of the coil.

The present invention affords positive control of the suction line valvewithout the employment of electromagnets or pilot valves. In the case ofmagnetic valves, the objectis to overcome the suction line pressure bymeans of magnetic power and unloaders. In the present invention, thehigh pressure of the liquid line is utilized to readily overcome thelesser pressure of the suction line.

In an ordinary installation employing a two inch suction line, apressure of one hundred fifty pounds on the liquid line, the totaldifierential in pressure available to actuate the suction line valve isapproximately four hundred It will be. that the present inventlon is notlimited to any partiwlar valve ormechanicalstructurebutisdirectedbroadiyto the employment of liquid linepressures to operate suction line alves in refrigeration systems. In thedram,'similar reference characters in the several figures indicatesimilar elements.

Figure. 1 is a. tic view of a refrigeration system employing the presentinvention.

Figure 2 is a central vertical sectional view of a pressure actuatedsuction stop valve constructed in accordance with this invention.

Figure3isahorlzontalsectionalviewtaken substantially on the line l-i-ofFigure 2.

Figureiisa'similarviewonthelinei-i of Figure 2.

The operation of the present invention maybereadflyunderstoodbyreferencetolqgurel in which compremor liii, drivenby motor IIIZ, forces com gas through pipe iii; to condenser IM. fiieliquid from condenser I54 passesinto receiver Hi5, thence through pipeM8 to pipes ill! and 4|. Pipe I01 leads to evaporators not shown.Magnetic liquid stop valve I08 is provided in pipe Ii to close it whenac- Since there can be no refrigera- I tuated by thermostat I". Theliquid passes through the control section of valve 0, thence throughpipe I! and float or thermal valve ill by which the liquid is fed toevaporator m as required.

Evaporator H2 is placed in the space to be refrigerated as for example abrine tank or a chamber. Gas passing from evaporator H2 passes throughpipe 4 into the suction cutoff of valve Ill, thence through pipe tocompressor 10 ilii. Pipe I I3 leads to the compressor from otherevaporators not shown. Motor ")2 is started by magnetic switch. H4controlled by thermostat "I9. 1

Valve H0 isshow'n in detail in Figures 2, 3,

and 4, and comprises in its construction a tubular main valve body Iconstituting the upper portion of the body or casing of the device andforming a longitudinal passage having upper and lower cylindricalchambers 2 and 3 and provided with a. gas inlet 4 and a gas outlet 5communicating with the gas inlet); passages 6 and 1 extending inwardlyfrom the gas inlet and the gas outlet and communicating with the uppercylindrical chamber 2. The gas inlet 4 is located at a higher elevationthan the gas outlet 5 and the upper cylindrical chamber 2 of the mainvalve body I is provided with a valve seat 8 located between the gasinlet 4 and the gas outlet 5 and adapted to receive an upper valve disk9 for closing comw munication between the gas inlet 4 and the gasoutlet. 5 for shutting oi! the flow of the gas through the suction linefrom the cooling or expansion coil of a refrigeration system to thecompressor'or condenser thereof.

The pressure actuated suction stop valve is applicable to refrigeratingsystems having a pointof controlled'varying pressures, the two pressuresbeing the evaporator and the condenser pressures.

The passage 6 extends directly from the gas inlet 0 l to the uppercylindrical chamber 1 and the passage 1 which extends inwardly from thegas outlet extends across the :main valve body I from the gas outlet 5to the opposite wail of the said body i and it communicates with areduced por- 5 tion ill of the upper cylindrical chamber 1. The valveseat 8 is'formed by a valve seat ring Ii which is threaded into anannular recess I 2 formed by an enlargement pf the reduced portion ll ofthe lower end ofthe cylindrical chamber 2.

-'l'he valve seat ring Ii is bevelled at its inner face at its upperedge and the upper valve disk 9 is correspondingly bevelled to fit thevalve seat.

Grooves II in the walls of upper valve,disk 9 serve to permit gas ebetween chamber 2 and passage 6 to equalize the pressure. The passage iis enlarged as illustrated at It, thus permitting pressure equalizationon all sides.

The upper valve disk I is urged downwardly by a coiled spring I! fittedin socket OI of the uppervalvedisklandheidinplacebyboss l0 intopcapli.'I'opcapliissecm-edtotheupper endofthemainvalvebodylbythreadedstuds i1and nuts i8. "lhe coiled spring positively closes the upper valve diskand while the presa sure actuated suction stop valve is preferablyarranged in a vertical position, it may, of course,

beau-ranged in any other desired position as the coiled spring II willpositively close the upper valve disk 9 and maintain the sameflrmlyagainst its seat 8 when the pressure in the liquid line is reducedas hereinafter fully explained. The top cap studs I! are fixed to theupper end of the main valve bpdyand'the nuts l8 engage the upper face ofthe top capwhich is pierced by the 1 lower lace with a central boss itinto the upper. end or the coiled ters the salne.'1'he's ald top capisalsoprovided at its lower iace with an annular rib It arrangedconcentric with the central boss II andadaptedtobearagainstatopcapgasket it which is fitted in an annularrecess 22 in the upper end lot themain valve body I. The annular rib 2|and the top cap gasket 2| tom a-gas tight joint between the top cap andthe main valve body to prevent the escape of gas.

When the upper valve disk is closed, it 01! communication between thegas inlet and the gas outlet and prevents the flow gas through thesuction line. The upper .valve disk is connected by a piston stem IIwith a piston head it which carries a lower valve disk 25 and whichoperates in a lower cylindrical chamber 3. The

ll piston stem 23 extends downwardly from the upper valve disk and isguided at I! in the main valve disk' body and its lower end ispreferably I" is opened to permit liquid to flow through the liquidlinetothe evaporator H1. 4

The check valve body is provided with a liquid inlet II and a liquidoutlet 41 and it has a liquid passage ll connecting the liquid inlet andthe 5 liquid outlet and consisting. of a horizontal branch or"portidnand a vertical branch or portion II. The horizontal branch or portionextends inwardly from the liquid inlet ll and the vertical branch 45extends upwardly from the inner-end oi the'horizontal branch or portion44 to the liquid outlet 42. The liquid inlet and the liquid outlet arethreaded tor; pipe connections and the gas inlet and the gas outlet arealso threaded for the same purpose. When liquid ows through the liquidline it enters the liqui inlet of the lower check valve body and passesthrough the passage 43 which connects the liquid inlet with the liquidoutlet and a portion oi the liquid also enters the passage 9| through achamber It communicating with passage 44 and having a lower reducedinlet threaded into the piston'head :p 41 provided t av zv seat as withwith a jam nut 28, but the stem II which is ll shown fitted in socket Q2of the upper valve disk llnaybeconnectedwitht liwr valve'diski and thelower piston head II in any other desired manner as will be readilyunderstood.

The piston head 24 is provided with piston rings 80 as and the lowervalve disk 25 cooperateswith a valve seat formed by a removable valveseat ring 3| preferably threaded into the main valve body i as indicatedat 82. The'lower edge of the valve seat ring II is bevelled to form thevalve I seat 30 and the lower portion a of the lower cylindrical chamberis enlarged forming an annular space below the valve seat surroundingthe lower valve disk 25 and the lower portion of the piston ll. go Thelower valve disk I! is oil-greater diameter than the piston head 24 andis bevelled as shown to cooperate with the bevelled valve seat. Thepiston 24 consists of a reduced cylindrical extenslon oi the lower valvedisk 25 and is preferably formed integral with the same. The lower endof the main valve body I is provided with an annular groove for-thereception of a check valve body gasket 85 and a check valve body 38 issecured to the lower end 0! the main valve body I by lower check valvestuds 3'! and nuts 38. The check valve body conforms to theconflgurationoi the main valve body and is provided at its upper endwith an annular rib I9 whichflts within the annular groove II o! thelower end of the main valve body and bears against-the lower-check valvebody gasket Ii. The studs 31 are fixed to the lower end 01' the mainvalve body and pierce portions oi the upper end of the check valve bodyand the nuts ll maintain the annular rib II in tight clamping engagementwith the lower check valve body gasket}! to term a liquid and gas tightconnection to prevent the escape of any liquid or gas from the device.The lower check valve bodyc'onstltutes the lower portion of the body ofthe device ,and it is 1 provided in its upper end with a circular recessII which communicates with a vertical liquidpassage 90 for admitting theliquid to the lower face of the lower valve disk for subjecting the sameand til piston head to the pressure of the ,liquid line forcausingsuchrpressure' to over come the action or, the coiled spring I!and open the upper valve disk {when the liquid stop valve liquid stopvalve is closed.

which a needle valve 49 cooperates for controlling the flow t the liquidthrough the passage 25 Q0 and the n 01' the liquid pressure to the lowervalve disk 25 and consequently the opening or the upper valve dish 9. Byadiusting the needle valve 49, the opening of the valve disk 9 forpermitting the flow ofthe gas through the '30 main valve body may beretarded to prevent damage to the valve by the high pressures eml l Thelower check valve body is also provided with a by-pass passage 50connecting the main liquid passage 43 with the chamber l6 and thepassage ll so that the liquid -may flow freely tromthe lower cylindricalchamber l of the main valve body into the liquid line when. the

The needle valve 48 has a threaded portion 5| which engages an upperthreaded portion 52 of a vertical opening or bore 53 in the lower end ofthe check valve body. This permits an adjustment of the needle valve 49with relation to the tapered lower end or valve seat of the reducedportion ll 0! the chamber 46 of the lower check valve body. The'lowerportion 54 of the 1 bore or opening 53 is threaded to receive a gland $5and packing 56 which is interposed between 5 the gland i5 and a stufllngbox washer i! to form a stuillngbox to provide a liquid and gas tightconnection or joint around the needle valve for preventing the escape orliquid or gas. The lower portion]! of the check valve body is reducedand exteriorly threaded at I! to receives lower cap ,60 interiorlythreaded at the upp end to engage the threads 59 o! the lower reducedportion 8! of the lower check valve body. A bottom cap gasket Ii isarranged between the upper edge of the bottom cap and the shoulder 62formed by a reduction of the lower portion of the lower check valvebody; 7

Check valves are provided in the ma n passage I and in the by-passpassage SI for purposes hereinafter described. The check va ve of themain liquid passage It comprises a check valve disk It and a valve seatI consisting of an interiorly bevelled portion oi a sleeve 85 arranged-in a boreor opening ll extending upwardly from c 43 and it forms ashoulder l1 surroundin g the upper end oi the vertical branch 45 oi. themain liquid passage and receiving a gasket which is engaged by the lowerend 01' the sleeve '5. The lower end of the sleeve II is reducedinteriorly and exterioriy to form an annular rib I! for engaging thegasket It. A retaining plug Ill is threaded into the upper end of thebore or opening it and engages the upper end of the sleeve 0!. Theretaining plug I. holds the sleeve tightly in engagement with the seatgasket 08. The sleeve is provided at the liquid outlet with oppositeopenings 1| and it has an exterior annular recess I! which provides anannular space or passage around the sleeve tor connecting the openingsII to facilitate tree passage 0! the liquid through the lower valvebody.

The by-pass check valve comprises a check valve disk 13 arranged upon acheck valve seat ll of a sleeve "I5 constructed similar to the checkvalve sleeve heretofore described and arranged in a vertical bore oropening 18 extending from the chamber 40 and the by-pass II to the upperend of the lower check valve body. The bore or opening 16 is 01. greaterdiameter than the chamber 46 to form a shoulder 11 on which is seated agasket It. The lower end of the sleeve is reduced to form a gasketengaging rib I9. Also the sleeve is provided with opposite openings 80and it has an exterior annular recess Ii forming a space around thesleeve at the said openings. The lower check valve body is provided withclean-out plugs 82 and I! mounted in threaded openings N and I which arearranged in line with the openings of the seat forming sleeves of thecheck valves.

The sleeve II is retained in the opening or bore I! by a retaining plugll threaded into the upper end of the bore or opening II and constructedsimilar to the threaded retaining plug 10. A filler block or piece I isinterposed between the retaining plug I. and the upper end of thesleeve.

The gas passes through the main valve body in the direction oi the arrowpointing toward gas inlet I in Figure 2 of the drawings and the liquidpasses through the lower check valve body in the direction 01' the arrowpointing toward liquid inlet ll in Figure 2 of the drawings, the liquidflowing to the right in the said figure and the gas to the lei't.Starting from a closed position with the magnetic liquid stop valve ofthe refrigeration system closed, the thermostat ot the reirigerationsystem opens the magnetic valve and permlts the high pressure liquid toextend as tar as the float valve on the expansion or cooling coil. Asthe liquid passes through the lower check valve body which with theparts carried thereby constitutes the control iy of the suction stopvalve, pressure is applied to the high pressure piston which opens thevalve on the suction line. when the desired temperature is reached inthe refrigeration chamber, the thermostat closes the liquid magneticstop valve and the float valve releases the pressure between themagnetic stop valve and the evaporating coil. The lowering or thepressure on the piston on the high pressure side or the suction stopvalve allows the suction stop valve to close and further refrigerationis stopped until the magnetic liquid stop Tvalve is again opened lay-thethermostat.

I The pressure of the liquid entering passageway 43 will cause a portionof the fluid to pass needle 2!, by which valve disk II will be raisedagainst the action of spring I! and thereby open suction valve I inpassageway I.

-When reirigeration is discontinued and the liquid stop valve closed.the pressures in the liquid line and the suction line will be balanceduntil after closing of suction valve 8, which closing should be ratherprompt for most emcient operachamber Ill and in all of the channels ofthe control section oi valve llil drops to the evaporator pressure. Itwill be readily appreciated that at the lower pressures the back row ofliquid through the small opening of needle valve 49 would be very slow.Since prompt response and consequent closing of the suction line isdesired, check valve I3 is provided. The weight oi piston 24 augmentedby spring I! causes the liquid in conduit to raise the relatively lightweight check valve disk 13 and permit the liquid from chamber 33 to passout through conduit Ill and thence out pipe 42 to the evaporator withoutdelay. Alter the piston has dropped. check valve disk 13 reseats andremains seated until again urged upwardly when the magnetic liquid stopvalve has opened and again closed.

Check valve 68 serves to prevent counterflow of gas through the lowercheck valve body when the refrigerating system is not in operation.

The pressure in the liquid line to the evaporator or cooling orexpansion coll will vary between the liquid cutoil' valve and the floator thermal expansion valve. Between these two points-the pressure willeither be that ol the condenser or liquid pressure or that 0! theevaporator or cooling coil, the pressure being dependent upon theopening and closing of the liquid stop valve which is determined by thedesired temperature in the refrigerated space through the action of thethermostat. when refrigeration is required and the liquid stop valve isopened. the condenser pressure is applied to the piston or the motionvalve which is greater than the combined pressure or the coiled springand the evaporator or gas pressure on the upper valve disk 9 causing thevalve disk 1 to open. The valve disk 9 remains in its open position aslong as liquid is fed to the evaporator coil. when reirigeration'isdiscontinued and the liquid stop valve closed, the pressure in theliquid line between the stop valve and the expansion or float valve isgradually reduced to the pressure inside of the evaporator and thispermits the suction stop valve to close. The opening movement of thevalve disk I is controlled by the needle valve of the control assemblyso that the valve disk 0 will open at the proper time with relation tothe flowoi the liquid through the liquid line.

. As the device is entirely enclosed. it will operate under any moistureconditions.

I claim:

1. A stop' valve eomprising a housing, a high pressure passage in saidhousing, a low pressure valve II, through liquid conduit II and into*passage in said housing, a val've normally seated is chamber "againstthe lower face oi valve disk to close said low pressure passage, apiston actuarcasoo ated means for unseating said low pressure valve.said piston actuated means provided with a piston operable in a chamberinterposed between said high pressure passage and said low pressurepassage. said piston chamber communicating with said high pressurepassage through a communication oriflce, an adjustable fixed needlevalve in said commimlcation orifice to control flow volme from said highpressure passage through said communication oriflce for timing actuationof said piston by fluid pressure provided by fluid passing from saidhigh pressure passage through said communication orifice to said pistonchamber, and a bypass between said high pressure pas-.

sage and said communication orifice having a pressure actuated checkvalve interposed therein operable to accelerate closing of said lowpressure valve upon-release of fluid pressure in said high pressuresection, and a check valve insaid high prqsure e to prevent counterflowof gas therethrough.

2. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve including a bodyportion having a gas inlet and a gas outlet for connection with thesuction line of the refrigeration system andprovided with a passageconnecting the gas inlet and outlet, a valve member operating betweenthe gas inlet and outlet for opening and closing communication betweenthe same, a spring for urging the valve member to its closed position,.apiston connected with the valve member, a body portion having a liquid efor connection with the liquid line of the refrigeration systemand-provided with a liquid conduit communicating with the liquid passageand arranged to deliver liquid pressure to the piston for actuating thesame to move the valve member to its open position, a by-pass passageconnecting the liquid conduit with the liquid passage, check valveslocated in the by-pass passage and in the liquid passage for preventingcounterflow oi gas through the said passages. said check valvescomprising check valve sleeves having interior valve seats, and checkvalve disks arranged within the sleeves cooperating with the valveseats, the last mentioned body portion being provided with openingsreceiving the valve sleeves.

3. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve including a bodyportion having a gas inlet and a gas outlet for connectlon with thesuction line of the refrigeration system and provided with a econnecting the gas inlet and outlet, a valve member operating betweenthe gas inlet and outlet for opening and closing communication betweenthe same, a spring for urging the valve member to its closed position, apiston connected with the valve member, a body portion having a liquidpassageior connection with the liquid line of the refrigeration systemand provided with a liquid conduit communicating with the liquid passageand arranged to deliver liquid pressure to the piston for actuating thesame to move the valve member to its open position, means forcontrolling the passage of liquid through the said conduit forcontrolling the opening movement of the valve member,'and meansincluding a by-pass between said conduit and said liquid passage and acheck valve interposed in said by-pass operable to quickly release theliquid pressure from said piston to accelerate closing of saidvalve, theinlet ti: said by-pass being located between said controlling means andsaid piston.

4. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve including a bodyportion having a gas inlet and a gas outlet for connection with thesuction line of the refrigeration system and provided with a passageconnecting the gas inlet and outlet, a valve member operating betweenthe gas inlet and outlet for opening and closing communication betweenthe same, a spring for urging the valve member to its closed position, apiston connected with the valve member, a body portion having a liquidpassage for connection with the liquid line of the refrigeration systemand provided with a liquid conduit communicating with the liquid passageand arranged to deliver liquid pressure to the piston for actuating thesame to move the valve member to its open position, a by-pass passageconnecting the liquid conduit with the liquid passage, and a check valvelocated in the by-pass passage, said check valve being automaticallyoperable by pressure of liquid returning from said liquid conduitwhereby pressure against said piston and closing of said valve betweenthe gas inlet and outlet is accelerated.

5. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve including a bodyportion having a gas inlet and a gas outlet for connection with thesuction line of the refrigeration system and provided with a passageconnecting the gas inlet and outlet, a valve member operating betweenthe gas inlet and outlet for opening and closing communication betweenthe same, a spring for urging the valve member to its closed position, apiston connected with the valve member. a body portion having a liquidpassage for connection with the liquid line of the refrigeration systemand provided with a liquid conduit communicating with the liquid passageand arranged to deliver liquid pressure to the piston for actuating thesame to move the valve member to its open position. an adjustable needlevalve for controlling the e of liquid through the said conduit forcontrolling the opening movement of the valve member, means for quicklyreleasing the liquid pressure against said piston to accelerate closingof the valve between said gas lnletand outlet, and a check valve in theliquid passage for preventing counterilow of gas therein, said checkvalve com prising a check valve sleeve having an interior valve seat,and a check valve disk arranged with in thesleeve and cooperating withthe valve seat.

6. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve including a bodyportion having a gas inletand a gas outlet for connection with thesuction line of the refrigeration system and provided with a passageconnecting the gas inlet and outlet, a valve member operating betweenthe gas inlet and outlet for opening and closing communication betweenthe same, a spring for urgin the valve member to its closed position, apiston connected with the valve member, a body portion having a liquid efor connection with the liquid line of the refrigeration system andprovided with a liquid conduit communicating with the liquid the liquidpassage, check valves located in the by-pass passage and in the liquidpassage for preventing counterflow of gas through the said passages,said check valves comprising check valve sleeves having interior valveseats, check valve disks arranged within the sleeves cooperating withthe valve seats, the last mentioned body portion being provided withopenings receiving the valve sleeves, retaining plugs threaded into thesaid openings for securing the sleeves in the said openings, and afiller block interposed between the check valve of the by-pass passageand the retaining plug associated with such check valve.

7. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve including a bodyportion having a gas inlet and a gas outlet for connection with thesuction line of the refrigeration system and provided with a passageconnecting the gas inlet and outlet, a valve member operating betweenthe gas inlet and outlet for opening and closing communication betweenthe same, a spring for urging the valve member to its closed position, apiston connected with the valve member, a body portion having a liquidpassage for connection with the liquid line of the refrigeration systemand provided with a liquid conduit communicating with the liquid passageand arranged to deliver liquid pressure to the piston for actuating thesame to move the valve member to its open position, a by-pass passageconnecting the liquid conduit with the liquid passage, check valveslocated in the by-pass passage and in the liquid passage for preventingcounterflow of gas through the said passages, said check valvescomprising sleeves having interlor valve seats and provided withopposite openings and having an exterior recess extending around eachsleeve, ,check valve disks arranged within the sleeves and cooperatingwith the valve seats, said last mentioned body portion having clean-outopenings communicating with the recesses of the sleeves, and clean-outplugs normally closing the clean-out openings.

8. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve includinga mainvalve body having a gas outlet and a gas inlet and a passage connectingthe same and provided with upper and lower cylindrical chambers andhaving valve seat rings mounted therein, an upper valve disk cooperatingwith the upper valve seat ring for opening and closing communicationbetween the gas inlet and the gas outlet, said upper valve disk havingwings guided in the upper cylindrical chamber, a lower valve diskcooperating with the lower valve seat ring and having a piston headoperating in the lower cylinder, a piston stem connecting the uppervalve disk with the piston head, a coiled spring arranged within theupper cylindrical chamber and hearing against the said wings for urgingthe upper lease the liquid pressure from said piston to accelerateclosing said uppeilvalve disk and a check valve in said liquid passageto prevent counterflow of gas therethrough.

9. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve including a mainvalve body having a gas outlet and a gas inlet and a passage connectingthe same and provided with upper and lower cylindrical chambers andhaving valve seat rings mounted therein, an upper valve disk cooperatingwith the upper valve seat ring for opening and closing communicationbetween the gas inlet and the gas outlet, said upper valve disk havingwings guided in the upper -cylindrical chamber, a lower valve diskcooperating with the lower valve seat ring and having a piston headoperating in the lower cylinder, a piston stem connecting the uppervalve disk with the piston head, a coiled spring arranged within theupper cylindrical chamber and bearing against the said wings for urgingthe upper valve disk to its closed position, a lower check valve body secured to the main valve body and having a liquid passage and a liquidconduit communicating with the liquid passage and arranged to deliverpressure to the lower valve disk and the piston head for opening theupper valve disk, a needle valve mounted in the lower check valve bodyand arranged to control the passage of liquid from the liquid passage tothe liquid conduit for controlling the opening movement of the uppervalve disk, and check valves for preventing counterflow of gas throughthe liquid passage and the liquid conduit.

10. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve including a mainvalve body having a gas outlet and a gas inlet and a passage connectingthe same and provided with upper and lower cylindrical chambers andhaving valve seat rings mounted therein, an upper valve disk cooperatingwith the upper valve seat ring for opening and closing communicationbetween the gas inlet and the gas outlet, said upper valve disk havingwings guided in the upper cylindrical chamber, a lower valve diskcooperating with the lower valve seat ring and having a piston headoperating in the lower cylinder, a piston stem connecting the uppervalve disk with the piston head, a coiled spring arranged within theupper cylindrical chamber and bearing against the said wings for urgingthe upper valve disk to its closed position, a lower check valve bodysecured to the main, valve body and having a liquid passage and a liquidconduit communicating with the liquid passage and arranged to deliverpressure to the lower valve disk and the piston head for opening theupper valve disk, a needle valve for controlling the flow of liquid fromthe liquid passage to the liquid conduit for controlling the openingmovement of the upper valve disk, said lower check valve body having abypass communicating with the liquid passage and with the conduit at apoint between the needle valve and the piston for permitting free flow01' liquid from the piston to the liquid passage, and check valves forpreventing counterfiow of gas through the liquid passage and the by-passpassage.

11. A pressure actuated suction stop valve for refrigeration systemshaving a suction line and a liquid line, said valve including a mainvalve body having a gas inlet and a gas outlet and a passage connectingthe same and provided with upper and lower cylindrical chambers andhaving valve seat rings mounted therein, an upper valve disk cooperatingwith the upper valve seat ring tor opening and closing communicationbetween the gas inlet and the gas outlet. said upper valve disk havingwings guided in the upper cylindrical chamber, a lower valve diskcooperating with the lower valve seat ring and having a piston headoperating in the lower cylinder, a piston stem connecting the uppervalve disk with the piston head, a coiled spring arranged within theupper cylindrical chamber and bearing against the said wings for urgingthe upper valve disk to its closed position, a lower check valve bodysecured to the main valve body and having a liquid passage and a liquidconduit communicating with the liquid passage and arranged to deliverpressure to the lower valve disk and the piston head i'or opening theupper valve disk, a needle valve forcontroilingflieflowofliquidiromtheliquidpassage to the liquid conduitfor controlling the opening movement or the upper valve disk. said lowercheck valve body having a by-pass communicating with the liquid passageand with the conduit at a point between the needle valve and the pistonfor permitting tree flow of liquid from the piston to the liquidpassage. check valves for preventing counterflow of gas through theliquid passage and the by-pass passage, a stuliing box to:- the needlevalve, and a bottom cap threaded on the end of the lower check valvebody and covering the needle valve.

EAR-RY W. KEVIN.

CERTIFICATE OF CORRECTION Patent No. 2,165,800.

June 27, 1939.

HARRY W. NEVIN.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 1;,

ond column, line 20, strike out the reference numeral 10; line 23, forthe word "row" read flow; and that the said Letters Patent should beread with this correction therein that the same may conform to'therecord of the case in the Patent Office.

Signed and sealed this 15th day of August, A. D. 1959.

(Seal) Leslie Frazer Acting Commissioner of Patents.

cooperating with the upper valve seat ring tor opening and closingcommunication between the gas inlet and the gas outlet. said upper valvedisk having wings guided in the upper cylindrical chamber, a lower valvedisk cooperating with the lower valve seat ring and having a piston headoperating in the lower cylinder, a piston stem connecting the uppervalve disk with the piston head, a coiled spring arranged within theupper cylindrical chamber and bearing against the said wings for urgingthe upper valve disk to its closed position, a lower check valve bodysecured to the main valve body and having a liquid passage and a liquidconduit communicating with the liquid passage and arranged to deliverpressure to the lower valve disk and the piston head i'or opening theupper valve disk, a needle valve forcontroilingflieflowofliquidiromtheliquidpassage to the liquid conduitfor controlling the opening movement or the upper valve disk. said lowercheck valve body having a by-pass communicating with the liquid passageand with the conduit at a point between the needle valve and the pistonfor permitting tree flow of liquid from the piston to the liquid 1:check valves for preventing counterflow of gas through the liquidpassage and the by-pass e, a stuliing box to:- the needle valve, and abottom cap threaded on the end of the lower check valve body andcovering the needle valve.

EAR-RY W. KEVIN.

CERTIFICATE OF CORRECTION Patent No. 2,165,800.

June 27, 1939.

HARRY W. NEVIN.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 1;,

ond column, line 20, strike out the reference numeral 10; line 23, forthe word "row" read flow; and that the said Letters Patent should beread with this correction therein that the same may conform to'therecord of the case in the Patent Office.

Signed and sealed this 15th day of August, A. D. 1959.

(Seal) Leslie Frazer Acting Commissioner of Patents.

